It seems like the AI is completely ignoring my captured extractors on neutral areas, and just let's me use them for the rest of the game. Also at least in my latest game, it did not care to capture the extractors next to it starting planet in three hours. This really makes the games too easy, at least on some maps. I don't think the correct behaviour would require any arcane AI coding skills, and would have thought a search had found many topics on this issue, but found none. I might have missed the topics still, of course.